The Cyberwock

Whenever The Cyberwock enters the battlefield,
exile the top X cards from each player's library,
where X is the amount of life paid to cast this spell.
You may cast any number of spells from among
those cards without paying their mana costs and you
may put any number of lands put into exile this way
onto the battlefield your control.

The Cyberwock has hexproof as long as it is
untapped.